DESCRIPTION: This T-32 training grant application seeks funding for years 16-20 on a previous successful program for training in Microbial Pathogenesis at Washington University of St Louis (WU). This training program integrates 28 faculty members from five different colleges at WU, Medicine, Pediatrics, Molecular Microbiology, Pathology, and Biology. The program provides training of postdocs who presently have Ph.D., M.D. or M.D./Ph.D. degrees, and graduate training leading to a Ph.D. in pathogenesis and host defenses in Infectious Diseases. Over the past 15 years that this training program has been in progress, numerous changes in the impact of infectious diseases and microbial pathogenesis have continued to underscore the importance of these diseases in the world. The emergence of new diseases such as Legionaries Disease, Lyme Disease, hepatitis C, and AIDS, coupled with the resurgence of old problems such as TB, infectious leukemias, the discovery of the infectious nature of gastric and duodenal ulcers, and the spread of antibiotic resistance have increased public attention of the serious threat to human health pose by infectious diseases. Greater understanding of the underlying biologic principles holds the best promise for development of new and innovative strategies for treatment and prevention of infectious disease problems. To this end, the program proposes to recruit promising young scientists to the field and train them in first rate laboratories involved in pathogenesis research. The Program in Microbial Pathogenesis and Host-Parasite Interactions at Washington University is presently the largest training program of its kind in the U.S. and this NIH grant has been a major mechanism of supporting M.D. postdoctoral fellows at WU during their training in basic laboratory investigations. Over the past five years WU has significantly increased the number of scientists working in the areas of microbial pathogenesis as an index of its importance and the university's commitment to this arena. This application is inter-departmental in nature, composed of five major participating units from which the faculty for this program have been drawn. They are: A) Division of Infectious Diseases which has two components, Clinical and Research. B) Department of Molecular Microbiology which has added 6 new faculty members over the past five years--of the 15 faculty in this department, 11 are participating faculty and currently is training 10 predoctoral and 37 postdocs fellows. C) The Department of Biology, has two faculty, Drs. Roy Curtiss (co-director of the training grant, and Dr. Josie-Clark-Curtiss. There are 14 postdocs of the program being trained in the Department of Biology. D) The Department of Pathology has four faculty in the training program and currently has 5 predoctoral and 9 postdoctoral fellows. E) Department of Pediatrics also has four participating faculty and is presently training 1 PhD student and 4 postdoctoral fellows in the training program. All Graduate students at WU are admitted to a superdepartment run by the Division of Biology and Biomedical Science (DBBS) and after matriculation each student is permitted to select a laboratory program to participate in. The 29 NIH-funded investigators in the Pathogenesis Training Program all participate in the didactic program of the DBBS. The program is directed by Dr. Eric Brown who is assisted by two co-directors, Drs. Charles Rice and Roy Curtiss III. This administrative structure remains from the past program except that Dr. Rice has replace Dr. S. Normark as co-director. The faculty, although drawn from the university departments listed above, are divided into 7 training disciplines: AIDS, Bacterial Pathogenesis, Clinical Investigations, Fungi and Mycobacteria, Host Defense, Parasitology, and Virology and training in this program is also provided in those areas. To foster interactions among such a diverse group, weekly seminars and journal clubs. The co-directors mentioned above are assisted by a steering committee composed of Drs. D. Russell, W. Goldman, D. Sibley, S. Hultgren, and T. Steinberg. This committee adviser the co-directors concerning appointments to the training grant, general supervision of progress of trainees, advising trainees regarding coursework and selection of theses, supervising postdoc committees, mediating difficulties, and acting as liaison between the training program and DBBS.